Substrate processing apparatus and substrate processing method

Abstract

This substrate processing apparatus supplies wafers W accommodated in a closed processing container 10 with ozone gas and steam for processing the wafers W. The apparatus includes an ozone-gas generator 40 for supplying the ozone gas into the processing container 10 , a steam generator 30 for supplying the steam into the processing container 10 and a steam nozzle 35 arranged in the processing container 10 and connected to the steam generator 30 . The steam nozzle 35 is equipped with a nozzle body 35 a having a plurality of steam ejecting orifices 35 f formed at appropriate intervals and a heater 35 h for preventing dewdrops of the steam from being produced in the nozzle body 35 a . Consequently, it is possible to prevent the formation of dewdrops of solvent steam, which may produce origins of particles in the closed processing container, unevenness in cleaning (etching), etc., and also possible to improve the processing efficiency.

1. A substrate processing method comprising the steps of:
 placing a substrate in a processing container; 
 supplying a processing gas into the processing container to establish, within the processing container, an atmosphere of the processing gas having a first pressure higher than atmospheric pressure; 
 generating a solvent vapor in a solvent vapor generator with fluid communication between the solvent vapor generator and the processing container being disconnected while monitoring, by using a sensor, the pressure of the solvent vapor in the solvent vapor generator; 
 comparing the pressure in the solvent vapor generator with pressure in the processing container supplied with the processing gas; and 
 based on the comparison result, connecting the fluid communication between the solvent vapor generator and the processing container, thereby supplying the solvent vapor from the solvent vapor generator into the processing container in which the atmosphere of the processing gas having the first pressure has been established, when the monitored pressure in the solvent vapor generator is higher than the pressure in the processing container supplied with the processing gas, 
 wherein the solvent vapor is water vapor, the solvent vapor generator being configured to heat water contained therein to generate water vapor, and wherein the processing gas is ozone gas. 
 
     
     
       2. A substrate processing method as claimed in  claim 1 , wherein the step of monitoring the pressure in the solvent vapor generator is carried out by firstly measuring temperature of the solvent vapor in the solvent vapor generator using a temperature sensor and secondly calculating the pressure in the solvent vapor generator based on the measured temperature. 
     
     
       3. A substrate processing method as claimed in  claim 1 , wherein the step of monitoring the pressure in the solvent vapor generator is carried out by firstly measuring temperature of a liquid solvent before vaporized in the solvent vapor generator using a temperature sensor and secondly calculating the pressure in the solvent vapor generator based on the measured temperature. 
     
     
       4. A substrate processing method of  claim 1 , further comprising the step of regulating pressure of the solvent vapor before the solvent vapor is supplied into the processing container, to a second pressure higher than the first pressure of the processing gas in the processing container. 
     
     
       5. A substrate processing method as claimed in  claim 4 , wherein the step of regulating pressure of the solvent vapor includes a step of discharging an amount of solvent vapor from a closed space filled with the solvent vapor to be supplied into the processing container in order to prevent the second pressure from exceeding a predetermined upper limit value. 
     
     
       6. A substrate processing method of  claim 1 , wherein the step of monitoring the pressure in the solvent vapor generator is performed using a pressure sensor. 
     
     
       7. A substrate processing method of  claim 1 , further comprising a step of monitoring the first pressure in the processing container, wherein, during the performance of the comparing step, the monitored first pressure in the processing container and the monitored pressure in the solvent vapor generator are compared.